Wire drawing machine



s. H. RICHARDS 2,138,327

Nov. 29, 1938.

WIRE DRAWING MACHINE Filed Oct. l1, 1937 2 Sheets-Sheet 1 I8 SAMUEL H. RICHARDS By 73M ATTQKNEYS Nov. 29, 1938. s. H. RICHARDS WIRE DRAWING MACHINE Filed Oct. l1, 1937 2 Sheets-Sheet 2 mvENT,

SAMUEL H. RICHARDS m A m u Patented Nov. 29, 1938 UNITED STATES PATENTF OFFICE Application October 11, 1937, Serial No. 168,483 In Great Britain ctobcr 12, 1936 2 Claims.

This invention relates to wire drawing machines and has particular reference to means for securing the end of the wire to a block upon which the wire is wound for the purpose of drawing it through a die.

In cases in which the wire to be drawn is too heavy to be pulled through the die by hand, preparatory to drawing upon the block a common method employed is to secure the end of the wire to a grip or dog connected to one end of a length oi' chain or wire cable, the other end of which is secured to the block. When the machine is started up the chain is rst wound upon the block and then the wire which is being drawn.

The chain may be permanently secured, to the block or may be detachably secured, in which latter case it is removed after a few turns of wire have been wound.

Both arrangements suier from the serious drawback that should the grip slip oil the wire during the initial drawing procedure, the chain with the grip on the end of it will ily outwards from the block and this may constitute a serious danger to the operator.

In addition, since the chain is fixed at a radial distance from the block centre equal to the block radius, the starting torque which the driving shaft must exert is relatively large. Moreover, after the block has been fully wound diillculty is frequently experienced in removing the grip owing to the tension exerted on it due to the tightness with which the wire is drawn.

The main object of the present invention is to provide an improved arrangement in which the drawbacks above referred to are obviated.

According to the present invention the block is freely rotatable around the driving shaft and the wire gripping device is secured to a chain or cable which passes freely through an aperture in the block and the further end of which chain or cable is secured either directly to the driving shaft or to a collar or drum rigidly mounted thereon and located within the block, stop means being provided to obstruct movement of the gripping device through or beyond the aperture.

With such an arrangement the chain or cable will remain-in position during the wire drawing process and the block may be recessed to accommodate the gripping device so as to prevent it protruding outwardly, or alternatively, in cases in which the chain is wound on a drum secured to the driving shaft and located within the block the gripping device may rest within the aperture; suitable stop means may be provided on the block adjacent the aperture to prevent the grip- (ci. 20s-zo) ping device passing around the annular space between the drum and the block.

In order that the invention may be more clearly understood, reference will now be made to the accompanying drawings wherein:

Fig. 1 shows an elevation of a wire drawing block incorporating the invention.

Fig. 2 is a vertical sectional elevation of the block shown in Fig. 1, but showing also a portion of the framework whereon the block is mounted.

Fig. 3 is a plan view of the block showing the position of the parts during the initial drawing operation, whilst Fig. 4is a similar view to Fig. 3, showing the positions of the parts after the driving shaft has made a partial revolution from the position of Fis. 3.

In the drawings, the reference I indicates the central driving spindle which is journalled at 2 in a hollow boss 3 projecting vertically from the framework or casing of the machine. 4 is a n inner winding drum which is mounted rigidly on the shaft I, whilst 5 represents the drawing block which is located outside of Athe drum 4 and is formed with a central hub portion 6 which is journalled at 1 and 8 upon the boss 3 of the framework. The upper portion of the winding block 5, it will be observed, is constituted by axially extending ribs 9, which construction is well known. The wire I0 is engaged by a gripping device II which is secured to one end of a chain I2, the other end of which chain is anchored at I3 to the drum l. 'Ihe drawing block 5 is provided with an aperture I4 through which the chain I2 passes from the outside of the block to the inside. At the commencement of a winding operation the parts will be substantially in the position shown in Fig. 3. When, however,

.the shaft I commences to rotate in a counterclockwise direction the gripping device II will be drawn into the aperture I4 until it assumes the position shown in Fig. 4.

It will be observed that the block 5 is formed with a shoulder I5 which projects inwardly on one side of the aperture Il, whilst the drum 4 is similarly formed with an external shoulder I6. The chain is of such a length that when the gripping device II is drawn into the aperture I4 it abuts against the shoulder I5 lso that when the spindle rotates the chain will draw the block round with it. -When the grippingdevice has reached the position shown in Fig. 4 winding of the wire upon the block 5 will commence.

It will be appreciated that with such arrangements should the gripping device become detached from thewire it would be prevented by the block from flying outwards as the gripping device will merely -be drawn into the aperture against the, shoulder I5 and the block carried around with the shaft by the drawing chain. In addition, the effective initial starting pull is appreciably increased since the radius at which the pull is exerted is only that of the shaft or inner drum as compared with that ofthe block in previous known arrangements. Moreover, in removing the grip at the end of a drawing operation it is merely necessary to rotate the block slightly in the winding direction to reduce the tension exerted on the grip so as to permit the grip to be detached from the wire, whereas in previously known arrangements in which the block is rigidly attached to the driving shaft such procedure is diillcult.

In some cases it may be desirable to construct the drum 4 so that the radius is relatively small at the point i3 but increases progressively in passing from that point around to the position occupied by the gripping device Il when it is drawn into the position shown in Fig. 4.

With such arrangement a high starting pull maybe exerted on the wire which will be gradually reduced during the time that the chain is wound upon the drum 4. Moreover the initial drawing speed is considerably reduced so that during this period the grip is less likely to be snatched oil" the wire.

A convenient form of gripping device is shown in which the dogs are housed in a substantially rectangular portion i1 which is integral with an end portion I8, the surface of which follows a spherical contour.

I claim:-

1. In a wire drawing machine a, driving shaft, a. hollow wire winding block independently rotatable about said shaft and having an aperture in its periphery, a drum member rigidly mounted on the shaft, said drum member being located within the block and spaced radially therefrom, a flexible connector passing through said aperture in the block periphery, means for anchoring one end of said connector to the drum periphery, a wire gripping device secured to' the other end of said connector, and stop means on the block adjacent said aperture therein, said stop means being adapted to obstruct movement of the gripping device around the annular space between the drum and the winding block, the length of said connector being such that in operation the gripping device is drawn against the stop means on the winding block and thereby applies driving torque to said winding block.

2. In a wire drawing machine a driving shaft, a hollow wire winding block independently rotatable about said shaft and having an aperture in its periphery, a drum member rigidly mounted on the shaft, said drum member being located within the block and spaced radially therefrom,

a flexible connector passing through said aperture in the block periphery, means for anchoring one end of said connector to the drum periphery, a wire gripping device secured to the other end of said connector, and stop means on the block adjacent said aperture therein, said stop means beng adapted to obstruct movement of the gripping device around the annular space between the drum and the winding block, the length of said connector being such that in operation the gripping device is drawn against the stop means on the winding block and thereby applies driving torque to said winding block, the head portion of said Wire gripping device which abuts against the stop means on the block following a spherical contour while said stop means is correspondingly shaped.

SAMUEL HUGH RICHARDS. 

